George piddington



UNITED STATES PATENT OFFICE.

GEORGE PIDDINGTON, OF OAVERSHAM, NEW ZEALAND.

LOCK.

SPECIFICATION forming part of Letters Patent No. 499,580, dated June 1?), 1893.

Application filed September 1,1891. Serial 110.404, 154. (No model.)

To aZZ whom it may concern:

Be it known that I, GEORGE Prnnrnoron, of Caversham, in the county of Otago and Colony of New Zealand, have invented a new and useful Improvement in Rim-Locks, which improvement is fully set forth in the following specification and accompanying drawings, in which Figure I is a side View of the interior of my improved rim lock; Fig. II, a horizontal section on line 00 w of Fig. I; Fig. III, a detail view of the lock-bolt, and Fig. IV, a detail view of the striking plate.

My invention relates to improvements in door locks of the class generally known as rim locks, and its object is to provide a simple, cheap and substantial device having all the advantages of a mortise lock in addition to other peculiar merits as herein described.

Referring to the accompanying drawings, A designates the box or casing which may be made of cast iron. The rear end is reduced in thickness and is fastened directly to the surface of the door-stile a. The front end is enlarged as shown and inserted in a recess formed in the corner of the door stile. The sliding latch-bolt B has its forward end, that is the part that enters the plate, off set or out of line with its shank as shown in Fig. II. By this means, when the doorcloses, the projecting end of the bolt enters the plate on the door jamb instead of passing outside of the frame and requiring a box staple, which is one of the objectionable adjuncts of the ordinary rim-lock. An anti-friction roller 1) is pivoted in the latch bolt, near its head, and plays on the inside of the case. The bolt is thus relieved from all friction with the side of the mortise through which it passes, and is free to move whenever its beveled end encounters the striking plate C. The plate is provided with a groove or channel 0 which forms a guide-way for the outer end of the bolt. The body of the bolt slides on a stud D which engages the slot 01.

The lock-boltE is shaped in the same manner as the latch-bolt and for a like purpose. Its upper edge is cutawayinfront formingashoulder e which, when the bolt is shot, engages the shoulder F on the latch bolt. It will be seen that when the door is locked the bolts co-operate and the latch-bolt cannot be withdrawn until the lock-bolt is thrown back by the action of the key. The latch-bolt may also be converted into a lock-bolt by turning the button f and bringing the cam G into engagement with the notch in the upper edge of the bolt.

The lock-bolt is provided near its center with integral studs 9 which engage slots H in the tumblers h. The said slots have enlarged rectangular ends as shown. The process of manipulating this bolt will be readily understood. The action of the key first llfts the tumblers and brings the horizontal portion of the slots into line with the studs. The key then engages and shoots the bolt. It will be observed that it is necessary to reglute the length of the key bit with particular reference to the location of the tumblers. If the bit be too short the tumblers will not be lifted sufficiently to release the studs. If too long, the studs will occupy the lower recesses in the slots and the bolt will be retained therein. A pin I connects the dependent rear ends of the tumblers and engages a retract-ile spring 1', the opposite end of which acts upon the latch-bolt.

The several advantages of my device will be apparent. It forms but a slight pro ection on the surface of the door. The rear end being semi-circular in form and the corners neatly rounded, no sharp angles protrude to catch and rend clothing. The exposed face of the box maybe ornamented and made attractive in various ways.

What I claim as new is-- The combination in a lock of acase, formed as shown and described, the sliding latchbolt provided with an anti-friction roller pivoted therein and a locking cam G, for engaging the latch bolt, said latch bolt formed with a dependent angle or shoulder adapted to engage the lock bolt, with a lock bolt off set at its forward end and provided on top with an angle or shoulder to engage and co-operate with the latch-bolt and having integral therewith studs g, the swinging tumblers formed with slots to engage the studs substantially as set forth.

In testimony that I claim the foregoing I have hereunto set my hand, this 6th day of July, 1891, in the presence of witnesses.

GEORGE PIDDINGTON.

Witnesses:

WILLIAM ROBERT GARRED, J. W. THOMPSON. 

